Although not intended to be confined to a suspension of piezoelectric resonators the invention arose through the problem associated with the connection of such resonators to electrically conductive supporting leads. Such resonators in general have been elastically supported by means of wires or thin ribbons for which the purpose is to assure an assembly which will resist forces arising from shocks due to acceleration generally encountered in applications such as in quartz timepieces, and at the same time to achieve the necessary electrical connections.
In most cases the attachment points of such leads must be located with considerable precision and normally correspond to places where vibration amplitudes are at a minimum. Such places are often determined by calculation and may be in the form of points which in fact correspond to nodal points.
In certain resonators operating at high frequencies, however, such places may be in the form of points, lines or surfaces in accordance with the type of resonator.
One currently used method for fastening the ends of the leads to the surface of the resonator is to use a welding or brazing alloy having a low fusion temperature. The extremity of the lead may in certain cases exhibit a flattened zone although this may not be necessarily the case. Herein the brazing or soldering alloy is applied as a wire or preform, and a soldering or brazing operation is effected by means of an appropriate heat source with or without the aid of a chemical fluxing agent.
In practice it is found that the dimensions fo the fastening vary according to the quantity of alloy utilized, the type of flux, the heating time, the quality of the surfaces and their degree of cleanliness. Under optimum conditions for the obtaining of a good joint the alloy shows a certain tendency to spread itself over the metallized surface of the resonator and it may be said that such alloy wets the surface.
The presence of this soldering or brazing alloy around the nodal points will influence in a negative fashion the resonator performance in view of the increase of the mass and the loss of energy due to internal friction in this mechanically imperfect material. Furthermore, the quantity of soldering or brazing alloy used for each operation is not uniform when such is applied in the form of a wire. Although preforms may eliminate this difficulty they are difficult to retain in place during the operation.
Accordingly, the purpose of the invention is to provide a method for suspending electrical components such as piezoelectric resonators, by means of electrically conducting leads in a manner to eliminate difficulties hitherto encountered.
A further object of the invention is to provide leads which will enable the improved suspension method to be applied in an industrially economic fashion.